With reference to FIG. 8 and FIG. 9, description is given of operation (broadcast information transmission method) in which a radio base station eNB divides broadcast information (BCCH: Broadcast Control Channel) into multiple segments (SU: Scheduling Units) and repeatedly transmits the multiple segments to multiple mobile stations UE by using multiple subframes, in a mobile communication system of the LTE (Long Term Evolution) system.
As shown in FIG. 8, a BCCH (broadcast information) can be transmitted by being mapped to a BCH (Broadcast Channel) and a PDSCH (Physical Downlink Shared Channel).
The radio base station eNB is configured to repeatedly transmit the BCH four times to each of the multiple mobile stations UE, by using six radio resource blocks (RB: Resource Block) in a middle part of the bandwidth of a corresponding cell, in a first subframe (subframe #0) of each radio frame.
Here, the radio base station eNB is configured to transmit basic information such as a physical parameter (cell bandwidth or the like), a system frame number (SFN: System Frame Number) and Value Tag, by the BCH.
In addition, the radio base station eNB transmits SU-1 including broadcast information (BCCH) not mapped to the BCH, in a predetermined subframe (e.g., subframe #5) by a PDSCH (Physical Downlink Shared Channel).
Here, the radio base station eNB is configured to transmit scheduling information of each SU (called a different SU, below) subsequent to a SU-1 (e.g., the size of the different SU, subframes in which the different SU is to be transmitted, the cycle in which the different SU is to be transmitted, and the like), by the SU-1.
Moreover, the radio base station eNB is configured to transmit the different SUs in accordance with the scheduling information specified by the SU-1.
In addition, as shown in FIG. 9, the radio base station eNB is configured to divide each different SU into multiple segments #1 to #3 and sequentially transmit the multiple segments #1 to #3 by subframes in a Window, if the different SU cannot be transmitted in 1TTI (Transmission Time Interval).
For example, as shown in FIG. 9, the radio base station eNB is configured to transmit the different SU, by subframes #X, #X+1 and #X+n in the Window.
However, in the conventional mobile communication system of the LTE system, the radio base station eNB can change subframes to which the multiple segments #1 to #3 are mapped and the size of each of the multiple segments #1 to #3 (segmentation method for the corresponding different SU), when repeatedly transmitting the multiple segments #1 to #3.
Accordingly, there is a possibility that the multiple segments #1 to #3 may have been changed in mapped subframe and size while being repeatedly transmitted. Hence, a problem arises that, even when failing to receive only one or some of the multiple segments, each mobile station UE cannot receive only the one or some segments failed to be received.    Non-patent Document 1: 3GPP TS36.300, “E-UTRA and E-UTRAN; Overall description; Stage 2”, v8.1.0.    Non-patent Document 2: 3GPP R2-073236, “Transmission of dynamic system information”, Ericsson.    Non-patent Document 3: 3GPP R2-072660, “RLC mode for system information delivery”, Panasonic, NTT DoCoMo.